This project encompasses a wide scope of statistical collaboration and consultation with Laboratories and Branches within the Division of Intramural Research (DIR), and with other units outside of NIH. Particular consideration is given to statistical planning and design of experiments, statistical analysis of data, and statistical inference. Our collaboration has involved eight Laboratories/Branches, and the scope of the studies has ranged from the coordination and statistical management of a complex clinical trial to consultation on the appropriateness of the statistical analysis used for small laboratory experiments. Examples of studies with DIR include a randomized clinical trial of felbamate for the treatment of intractable partial seizures (MN); statistical aspects of the epidemiology of Creutzfeldt-Jakob disease with emphasis on case clustering (LCNSS); development of multi-state proportional hazards models with time-dependent covariates for time to stroke (NE); comparison of mechanical and electrical evoked blink reflexes in dysphonic patients and normal subjects (CNP); IL2 treatment of brain tumors in animal models (SN); identification of risk factors for febrile seizures with a population based case- control study of six cities in China (NE); stereotactic implantation of dispersed cells into the rat brain with focus on placement and survival (SN); comparison of Parkinson's disease prevalence for blacks and whites in Copiah County with those of a defined population of Nigeria (NE); comparison of tremor in a patient with Parkinson's disease before, at the time of, and after adrenal tissue implant (SN); examination of blood and CSF for catecholamine, neuropeptide and amino acid levels in epilepsy patients at baseline and postictal periods (MN); and identification of prognostic covariates for intractability in complex partial seizure patients (MN).